Age related cognitive impairments and assistive web-base technology

Several researchers argue that age related cognitive impairments have detrimental affect on use of web services by older adults. However little and systematic applied research has been conducted on how age related cognitive impairments might affect the usage of web services by older adults. Undoubtedly, understanding the relationship between the cognitive changes that accompany aging and their impact on older adults’ usage of web services will be beneficial for designing web services for this group. The paper demonstrates how such understanding has been employed to develop an assistive technology in order to improve older adults’ interaction with online forms

Transformational government and assistive web base technologies

Transformational government has been on the European agenda for several years. However, progress towards realising the full potential of ICT to transform public services for older adults with age related cognitive impairments has been very limited. Highlighting such limitations this paper demonstrates how assistive web base technologies can be developed to improve the public services for older adults with age related cognitive impairments. However the paper argues that these transformations can be obstructed if there is no strong leadership and political commitment from people at many levels in public sectors and governments

Signal Attenuation Modelling in WLAN Positioning

Wireless Local Area Networks (WLAN), as the most widely used indoor positioning technology, can localise users by measuring the Received Signal Strength (RSS) from multiple Access Points (AP). The challenges of this approach are that measuring RSS can be easily affected by several parameters, including how the users hold the device, e.g. device orientation, and that accurate maps of RSS are required. This paper (A) introduces a bell-curve model of signal attenuation from orientation, allowing more accurate RSS measurement, and (B) identifies collinearity issues with a path-loss model used to automatically create RSS maps, suggesting a simpler and more robust alternative

The Concordat: supporting the development of contract research staff

This presentation was given by Dr Lorna Lines, the Head of Staff Development at Brunel University, at the BRAM-NET meeting held on the 4th July 2011. The event was organised by Dr Rosa Scoble and hosted at Brunel University. BRAM-NET (The Brunel Research Administrators & Managers Network) is a forum to share best practice and information on new initiatives between colleagues supporting research in the centre and academic areas at Brunel University

Atomic-scale compensation phenomena at polar interfaces

The interfacial screening charge that arises to compensate electric fields of dielectric or ferroelectric thin films is now recognized as the most important factor in determining the capacitance or polarization of ultrathin ferroelectrics. Here we investigate using aberration-corrected electron microscopy and density functional theory how interfaces cope with the need to terminate ferroelectric polarization. In one case, we show evidence for ionic screening, which has been predicted by theory but never observed. For a ferroelectric film on an insulating substrate, we found that compensation can be mediated by interfacial charge generated, for example, by oxygen vacancies.Comment: 3 figure

Elastic effects of vacancies in strontium titanate: Short- and long-range strain fields, elastic dipole tensors, and chemical strain

We present a study of the local strain effects associated with vacancy defects in strontium titanate and report the first calculations of elastic dipole tensors and chemical strains for point defects in perovskites. The combination of local and long-range results will enable determination of x-ray scattering signatures that can be compared with experiments. We find that the oxygen vacancy possesses a special property -- a highly anisotropic elastic dipole tensor which almost vanishes upon averaging over all possible defect orientations. Moreover, through direct comparison with experimental measurements of chemical strain, we place constraints on the possible defects present in oxygen-poor strontium titanate and introduce a conjecture regarding the nature of the predominant defect in strontium-poor stoichiometries in samples grown via pulsed laser deposition. Finally, during the review process, we learned of recent experimental data, from strontium titanate films deposited via molecular-beam epitaxy, that show good agreement with our calculated value of the chemical strain associated with strontium vacancies.Comment: 14 pages, 11 figures, 4 table

Domain Size Dependence of Piezoelectric Properties of Ferroelectrics

The domain size dependence of piezoelectric properties of ferroelectrics is investigated using a continuum Ginzburg-Landau model that incorporates the long-range elastic and electrostatic interactions. Microstructures with desired domain sizes are created by quenching from the paraelectric phase by biasing the initial conditions. Three different two-dimensional microstructures with different sizes of the $90^{o}$ domains are simulated. An electric field is applied along the polar as well as non-polar directions and the piezoelectric response is simulated as a function of domain size for both cases. The simulations show that the piezoelectric coefficients are enhanced by reducing the domain size, consistent with recent experimental results of Wada and Tsurumi (Brit. Ceram. Trans. {\bf 103}, 93, 2004) on domain engineered $BaTiO_{3}$Comment: submitted to Physical Review